* {
    margin: 0;
    padding: 0;
}

html, body {
    height: 100%;
    width: 100%;
    display: flex;
    flex-flow: column;
    overflow: auto;
}

a {
    text-decoration: none;
    color: black;
}

.head {
    padding: 10px;
    height: 55px;
    background-color: #559677;
    position: relative;
    font-family: "隶书";
    font-size: 20px;
}

.head a {
    position: absolute;
    top: 20px;
    right: 25px;
}

.body {
    flex-grow: 1;
    width: 100%;
    height: 85%;
}

.content {
    height: 100%;
    background-color: #ffffff;
    flex-grow: 1;
    overflow: auto;
}

.nav {
    float: left;
    width: 8em;
    height: 100%;
    background: #cde4da;
    border-bottom: black;
}

.nav ul {
    list-style-type: none;
    line-height: 3em;
    overflow: hidden;
    text-align: left;
}

li ul a {
    display: block;
    border: 1px solid #CCC;
    font-size: 13px;
}

.nav2 {
    display: none;
    background: #F5F5DC;
}

a:link, a:visited {
    display: block;
    text-align: center;
    color: black;
    text-decoration: none;
}

a:hover, a:active {
    background: #94aa64;
}

.current .content {
    display: block;
}

.systemTime{
    display: inline-block;
    float: right;
    margin: 0 40px 0 0;
}

h1{
    display: inline-block;
}